Sanic is a Flask-like Python 3.5+ web server that's written to go fast. It's based off the work done by the amazing folks at magicstack, and was inspired by this article: https://magic.io/blog/uvloop-blazing-fast-python-networking/.
On top of being flask-like, sanic supports async request handlers. This means you can use the new shiny async/await syntax from Python 3.5, making your code non-blocking and speedy.
All tests were run on a AWS medium instance running ubuntu, using 1 process. Each script delivered a small JSON response and was tested with wrk using 100 connections. Pypy was tested for falcon and flask, but did not speed up requests.
Server Implementation Requests/sec Avg Latency Sanic Python 3.5 + uvloop 29,128 3.40ms Wheezy gunicorn + meinheld 20,244 4.94ms Falcon gunicorn + meinheld 18,972 5.27ms Flask gunicorn + meinheld 4,988 20.08ms Aiohttp Python 3.5 + uvloop 2,974 33.49ms Hello World